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Title: Enhanced charge storage of nanometric ζ-V 2 O 5 in Mg electrolytes
V 2 O 5 is of interest as a Mg intercalation electrode material for Mg batteries, both in its thermodynamically stable layered polymorph (α-V 2 O 5 ) and in its metastable tunnel structure (ζ-V 2 O 5 ). However, such oxide cathodes typically display poor Mg insertion/removal kinetics, with large voltage hysteresis. Herein, we report the synthesis and evaluation of nanosized ( ca . 100 nm) ζ-V 2 O 5 in Mg-ion cells, which displays significantly enhanced electrochemical kinetics compared to microsized ζ-V 2 O 5 . This effect results in a significant boost in stable discharge capacity (130 mA h g −1 ) compared to bulk ζ-V 2 O 5 (70 mA h g −1 ), with reduced voltage hysteresis (1.0 V compared to 1.4 V). This study reveals significant advancements in the use of ζ-V 2 O 5 for Mg-based energy storage and yields a better understanding of the kinetic limiting factors for reversible magnesiation reactions into such phases.  more » « less
Award ID(s):
1809866
PAR ID:
10252898
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Nanoscale
Volume:
12
Issue:
43
ISSN:
2040-3364
Page Range / eLocation ID:
22150 to 22160
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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